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Full Discussion: File Descriptors
Top Forums UNIX for Advanced & Expert Users File Descriptors Post 33116 by Perderabo on Tuesday 17th of December 2002 11:31:09 AM
Old 12-17-2002
You're worried about file descriptors?
File descriptors use a trivial amount of memory and I don't understand what it is that you're worried about. Each time you remove a file descriptor from your system you get back the space required to store two shorts and one pointer. Are you really that tight on swap space?

Your average fd will also require a file table entry, but even that isn't a real big deal. If I open() a file, and then dup()it 100 times, I will have 101 fd's all pointing at the same file table entry. That would be a little crazy, but lots of processes have stdout and stderr pointing to the same file table entry, so assuming a correspondence between fd's and open files is wrong.

Any process can change its soft limit to any value that does not exceed its hard limit. Any process may lower its hard limit. A root process can raise its hard limit.

We have some 5.5.1 systems and we use lsof on them all the time. But pfiles in included with 5.5.1 and might be a better choice for you anyway.
 

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LEARN ABOUT OPENSOLARIS

cvcredir

cvcredir(7D)							      Devices							      cvcredir(7D)

NAME

       cvcredir - virtual console redirection driver

DESCRIPTION

       The  cvcredir  virtual console redirection driver is a STREAMS-based pseudo driver that supports the network console provided on some plat-
       forms. The cvcredir driver interfaces with the virtual console driver cvc(7D), and the  virtual console	daemon,  cvcd(1M).

       The  cvcredir driver receives console output from cvc and passes it to  cvcd. It receives console input from  cvcd and passes it to  cvc.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |Sun    Enterprise     10000  |
       |			     |servers,	 Sun   Fire   15K  |
       |			     |servers			   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcvc.u 		   |
       +-----------------------------+-----------------------------+

SEE ALSO

       cvcd(1M), attributes(5), console(7D), cvc(7D)

       Sun Enterprise 10000 SSP Reference Manual

       Sun System Management Services (SMS) Reference Manual

SunOS 5.11							    15 Sep 2000 						      cvcredir(7D)
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